Method and composition for improving milling products



Patented at. 27, 1949 PATENT OFFICE METHOD AND COMIPOSITION FOB DIPBOV-ING MILLING PRODUCTS Frederic 1!. Penn, Dallas, Tex.

No Drawing. Application June 6, 1939, Serial No. 277,783

12 Claims.

My invention relates tothe improvement of wheat flour and other millingproducts, including the baking and keeping qualities thereof, and moreparticularly has reference to a method and composition for thesimultaneous bleaching'and ageing or maturing of flour and the like.

According to present commercial practice, flour is bleached and aged inseparate stages of treatment. The initial treatment is accomplished withgaseous nitrogen trichloride, which matures the flour. Nitrogentrichloride, in addition to being a maturing agent, also possessesbleaching properties, but when used in sufllcient amount to obtain acomplete commercial bleach, injures the quality of the flour. Therefore,for this reason nitrogen trichloride'is used in an amount notsubstantially in excess of that required to mature or age the flour, andthe necessary additional bleaching is obtained by a subsequent treatmentwith benzoyl peroxide, which has no maturing properties. While thelastmentioned step is relatively simple, the gas treatment is quitecumbersome, requiring special contacting apparatus andcorrosion-resistant equipment and accurate control over the gas, whichpresents many hazards and difficulties in use.

It is an object of this invention to bleach and age flour and the likein a single operation and to provide a finely divided or powderedcomposition which, when intimately mixed with the flour, functions toeffect a simultaneous bleaching and ageing of the milling product. Theflour is thus improved in the two respects mentioned by the simpleexpedient of mixing the solid composition therewith and allowingsufflcient time for the desired effects to take place.

In my prior Patents Nos. 2,158,588 and 2,158,589, I have shown thatsimultaneous bleaching and ageing of flour and the like can be obtainedby means of a powdered mixture of a bromate or lodate with an activeorganic peroxide, the latter seemingly functioning as an activator oraccelerator for the solid bromates and iodates in their maturing of thedry milling product. I have now found that water soluble saltscontaining heavy metals, in their acid radicals, in powdered form,similarly function with the active organic peroxides to bring about asimultaneous bleaching and ageing of flour and other milling products.

Accordingly, the, solid bleaching and maturing composition of thepresent invention comprises a pre-formed mixture of a. powdered watersoluble salt containing a heavy metal in its acid radical and an activeorganic peroxide, that is, an organic peroxide which is s'ufficientlyactive in powdered form'to eflfect at least a flour bleach. I Potassiumvanadate in powdered form is the preferred reagent for use with theactive organic peroxide; sodium tungstate and potassium manganate areillustrative of other water soluble heavy metal salts suitable for usein powdered form with the active organic peroxide.

As in my prior patents referred to, only certain organic peroxides aresufficiently active to cooperate with postassium vanadate and'likecompounds to effect the simultaneous bleaching and maturing, these beingthe aromatic and fatty acid peroxides which have suflicient activity inpowdered form to accomplish at least a 90% flour bleach. Benzoylperoxide is the preferred aromatic peroxide while cinnamyl peroxide andphenyl acetyl peroxide are other aromatic peroxides which I have foundto be of suflicient activity and flour bleaching power for use withpotassium vanadate and the like in accordance with the invention.Suitable active .fatty acid peroxides of sufiicient bleaching power formy purpose are stearyl peroxide, lauryl peroxide and palmitic acidperoxide. These aromatic and fatty acid peroxides functionwith thefinely divided or powdered salt to bring about a commerciallysatisfactory maturing and bleaching of dry flour. I believe that I amthe first to discover that the active aromatic and fatty acid peroxideshave the effect of increasing the maturing action of powdered potassiumvanadate and the like upon dry milling products.

In practicing the method of this invention, the bleaching and ageingcomposition is fed directly into the flour at any convenient pointduring the milling operation and intimately mixed therewith, by means ofpowder feeding machines now used in the mills, in the proportion ofabout onehalf ounce to 196 pounds of flour. For thorough distribution ofsuch small amounts of the composition in .the flour, the compositionshould be in the form of a dry free-flowing. finely divided powder. Asatisfactory bleaching and ageing is obtained by exposure of the flour.to the action of the composition for about twenty-four hours.

As illustrative of the preparation of a preferred composition, drypowdered commercial grade dicalcium phosphate or other suitable carrieris added to an equal weight of dry commercial grade granular benzoylperoxide and the mixture ground to the desired fineness. With the powderthus obtained there is now mixed dry powdered potassium vanadate in theproportion of six parts potassium vanadate to ninety parts of theperoxide-phosphate mixture. The resultant mixture is then ready for useas a flour bleachportion of peroxide, potassium vanadate and carrier, aswell as the amount of the composition required for eflective bleachingand ma turing, should be determined by tests in particular cases. Insome instances for certain kinds of flour the proportion of potassiumvanadate may be increased to about eight parts to ninty parts of theperoxide-phosphate mixture and in other instances the amount ofpotassium vanadate may be decreased to about four parts to ninety partsof the peroxide-phosphate mixture. Ordinarily the proportion of sixparts of potassium vanadate with ninety parts of the mixture of equalweights of benzoyl peroxide and dicalcium phosphate is satisfactory formany of the various grades of flour. The proportions here stated are byweight.

The compositions of this invention improve the color and bakingqualities of the flour. Loaf volume is one of the most important, if notthe most important, indication for determining the value of the bakingqualities of flour. The volume of the baked loaf of bread is measured incubic centimeters and denotes the exact size of the loaf produced. Smallvolume, as obtained 'with untreated or unmatured flour, indicates lowbaking strencth, while large volume indicates high baking strength,which is apparently brought about by the maturing of the flour.

The followingtabulations show, by comparison, the advantages andeffectiveness of my composition. Table I deals with a hard wheat bakersflour and Table II with a blend of hard and soft wheat flour. The tablesshow the amounts of benzoyl peroxide and potassium vanadate used in thetests. In each case where benzoyl peroxide was employed, it was mixedwith an equal weight of dicalcium phosphate as a carrier. This is notindicated in the tables for sake of simplification. The laboratory testswere performed on amounts of fresh milled flour such that the treatmentscorrespond to the use of about one-half ounce of the compositions per196 pound barrel of flour.

TABLE I Hard wheat bakers flour Loaf volume. .5 353 Texture c. c.

Untreated l 710 None 92 Laboratory treated benzoyl peroxidc 45 gm.,potassium vanadate 3 gm 765 99 99 Laboratory treated benzoyl peroxide 45gm 668 98 95 Laboratory treated potassium vanadate 3 gm 740 None 98TABLE II Blend hard and soft wheat flour Loaf volume, 5 3:2 TextureUntreated I 620 None Laboratory treated benzoyl peroxide 45 gm.,potassium vanadate 3 gm 645 99 98 Laboratory treated benzoyl peroxide 45gm 583 98 Laboratory treated potassium vanadate 3 gm 635 None 98Illustrative of the valuations of the tests: The loaf volume obtainedwith untreated hard wheat bakers flour, which is fresh milled flourwithout any kind of treatment, is 710 c. c. The same untreated freshmilled hard wheat bakers flour laboratory treated with the benzoylperoxide, potassium vanadate composition yields a loaf vplete commercialbleach of the flour yields a loaf volume of 668 c. c., a reduction of 42c. c. in volume less than is obtained with untreated flour. Laboratorypotassium vanadate treated hard wheat flour yields a loaf volume of 740c. c., an increase in volume of 30 c. 0. above the volume obtained withuntreated hard wheat flour.

According to the tests, benzoyl peroxide when used alone and insuflicient quantity for a complete bleach of the flour reduces the loafvolume, Potassium vanadate when used alone matures the flour somewhatbut not to as great an extent as when mixed with the peroxide and itdoes not have any bleaching effect. When benzoyl peroxide and potassiumvanadate in combination are incorporatedinto the dry flour during themilling process a complete bleach and color removal is obtained with anincrease in loaf volume which is in excess of the volume obtained wheneither potassium vanadate or benzoyl peroxide is used alone.

In'the appended claims I have characterized the organic peroxides asactive and as having substantial flour bleaching properties in order todistinguish from those organic peroxides which are of insumcientactivity and bleaching power to effect a commercial bleach. Bysubstantial flour bleaching properties is meant the ability to bleachflour satisfactorily for commercial purposes, that is, to efiect atleast a 90% bleach.

Having described my invention, I claim:

1. A method for improving wheat flour and other milling products whichcomprises intimately mixing with the dry milling product a powderedwater soluble salt containing a heavy metal in its acid radical and apowdered active organic peroxide having substantial flour bleachingproperties, the peroxide being in sufficient amount to bleach themilling product and said salt being in suflicient amount to increase theloaf volume factor of the milling product, and subjecting the millingproduct in dry form to the simultaneous action of said salt and peroxidefor a suflicient time to bleach and mature the product.

2. A method for improving wheat flour and other milling products whichcomprises intimately mixing with the dry milling product a powderedwater soluble salt containing a heavy metal in its acid radical and apowdered active aromatic peroxide having substantial flour bleachingproperties, the'peroxide being in suflicient amount to bleach themilling product and said salt being in suflicient amount to increase theloaf volume factor of the milling product, and subjecting the millingproduct in dry form to the simultaneous action of said salt and peroxidefor a suflicient time to bleach and mature the product.

3. A method for improving wheat flour and other milling products whichcomprises intimately mixing powdered benzoyl peroxide and a powderedwater soluble salt containing a heavy metal in its acid radical with thedry milling product, the peroxide being in suflicient amount to bleachthe milling product and said salt being in sufficient amount to increasethe loaf volume factor of the milling product, and subjecting the latterin dry form to the simultaneous action of the peroxide and said salt fora sufficient time to bleach and mature the milling product.

4. A method for improving wheat flour and" other milling products whichcomprises intimately mixing powdered benzoyl peroxide and potassiumvanadate with the dry milling product, the peroxide being in sufllcientamount to bleach the milling product and said vanadate being insufilcient amount to increase the loaf volume factor-of the millingproduct, and subjecting the latter in dry form to the simultaneousaction of the peroxide and potassium vanadate for a sufiicient time tobleach and mature the milling product.

5. A method for improving wheat flour and other milling products whichcomprises intimately mixing powdered benzoyl peroxide and sodiumtungstate with the dry milling product, the peroxide being in sufiicientamount to bleach the milling product and said tungstate being' insufficient amount to increase the loaf volume factor of the millingproduct, and subjecting the latter in dry form to the simultaneousaction of the peroxide and sodium tungstate for a sumcient time tobleach and mature the milling product.

. 6. A method for improving wheat flour and other milling products whichcomprises intimately mixing powdered benzoyl peroxide and potassiummanganate with the dry milling product, the peroxide being in suflicientamount to bleach the milling product and said manganate being insuflicient amount to increase the loaf volume factor of the millingproduct, and subjecting the latter in dry form to the simultaneousaction of the peroxide and potassium manganate for a sufiicient time tobleach and mature the milling product.

7. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of a water soluble salt containing a heavymetal in its acid radical and an active organic peroxide havingsubstantial flour bleaching properties, said salt being in sufiicientquantity to overcome the loaf volume reducing factor of the peroxide.

8. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of a water soluble salt containing a heavymetal in its acid radical and an active aromatic peroxide havingsubstantial flour bleaching properties, said salt being in sufiicientquantity to overcome the loaf volume reducing factor of the peroxide.

9. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of a water soluble salt containing a heavymetal in its acid radical and benzoyl peroxide, said salt being insufficient quantity to overcome the loaf volume reducing factor of theperoxide.

10. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of benzoyl peroxide and 'a sufficientquantity of potassium vanadate to overcome the loaf volume reducingfactor of the benzoyl peroxide.

11. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of benzoyl peroxide and a suificientquantity of sodium tungstate to overcome the loaf volume reducing factorof the benzoyl peroxide.

12. A flour bleaching and maturing composition comprising a dryfree-flowing powdered mixture of benzoyl peroxide and a sufiicientquantity of potassium manganate to overcome the loaf volume reducingfactor of the benzoyl peroxide.

FREDERIC H. PENN.

